1. Field of the Invention
This invention relates to operating levers for vehicles and is particularly concerned with such levers as are commonly used in the control of a vehicle throttle setting, vehicle brake control and/or vehicle clutching operations.
More particularly, the invention is related to lever extensions employed to extend the length of existing levers and/or to make actuation of such levers and the particularly the holding of such levers for an extended period of time, more comfortable for a user.
While generally making it easier for an operator to manipulate control levers extensions do not provide the same degree of comfort for all users. The size of a user's hand and the reach of the user's fingers and thumbs varies from user to user.
2. Description of the Related Art
It has been recognized in the past that thumb operated throttle control levers commonly used on all-terrain vehicles, snowmobiles, personal water-craft and many other vehicles are often difficult to hold in a set position since the user's thumb may tire and release the throttle lever. This is particularly true when the throttle lever is being held for slow vehicle travel and when the pivoting end of the lever is at its greatest distance from a handgrip being grasped by the vehicle user, thus requiring maximum stretch by the user's hand to hold the control lever in position.
Even if the user is not holding the throttle lever for slow vehicle travel the hand stretch required to hold the lever in an open throttle position may be very tiring, particularly for persons having small hands. A user of a vehicle equipped with brake control levers or clutch control levers and having small hands may also find it difficult to operate the brakes or clutch of the vehicle.
In U.S. Pat. No. 5,078,023 it is recognized that the thumb of a user of a vehicle equipped with a conventional throttle lever will often tire when the lever is actuated, particularly at low throttle settings when a wide spread between hand and thumb is required. The patent discloses use of primary and secondary pivoted levers to reduce the thumb pressure required as the throttle is opened and held during vehicle travel.
U.S. Pat. No. 5,758,364 also recognizes that a user's hand may tire when actuating the throttle lever of a snowmobile. The patent discloses a glove to be worn by the user of the vehicle and having a strap extending between the forefinger and the thumb of the glove. The strap engages the throttle lever such that as the user's gloved hand grasps and rotates on the handgrip of a snowmobile the strap engages and actuates the throttle lever.
U.S. Pat. No. 5,775,167 discloses use of a finger operated control lever for snowmobiles and other vehicles, which is a secondary acceleration device to the primary thumb operated throttle control lever of the vehicle. When the operator's thumb becomes tired, the finger throttle is used to continue riding while resting the thumb.
U.S. Pat. No. 6,494,113 discloses an extension attachment that can be used with the operating levers of a great many different types and models of vehicles having thumb, finger and hand operated control levers. When used, the extension lever may decrease the travel distance required for lever movement during control operations and allows a user to operate the control lever with the palm of the hand, after initiating pull on the extension lever with the thumb, rather than relying on a spread thumb for continued control lever operation.
The extension lever is made of durable materials and is molded to have a hand engaging extender and hinged attachment plates with individual segments to facilitate securement of the extender as a continuation of the control lever to which the extension lever is attached. A shoulder provided on at least one attachment plate extends beneath control lever structure to prevent turning of the extension lever relative to the control lever.